Wednesday, 11 April 2012

Loading catapult: Put the marble
into the cup via a drop chute or similar which is easy enough.

Achieving correct tension:

Could be setup before the machine
has started or we might have a cog that winds the arm back. Best to arm it before hand unless we’re using
multiple marbles that are going to be following each other. In that case something that is able to reload
itself is going to be a priority.

Trigger mechanism:

At it’s most simple a piece of string
could restrain the arm of the catapult and, at the proper time the string is
either snapped by a blade or burnt by a candle

Once the string has been broken
the candle will need to be doused. So
ideally what we need is a conveyor belt that stops when it is time to burn the
string and starts when the string is gone.
It will be a good look if we manage to douse the flame in a candle of
water.

We could use the trigger string
to act as a halter for the candle if it were to be attached to a toy car and
thus achieve movement. Once the string
has gone then the car is free to travel upon it’s merry way and sink in a
watery grave.

PIPE AND CUP

Image 1:
Ball enters piping and gathers speed which throws it into the cup.

Image 2:The cup is balanced on an axle
and the weight of the marble dislodges the cup which moves it down and the
counterweight up.

Image 3:When the cup reaches it tips
over, allowing the marble to continue on its way

EGG CARTON CAR

String
attached to both ends of toy car.

The forward
one is attached to a weigh while the rear one is just long enough to allow the
car to tip over the edge of the track and once again allows the marble to roll
free

PAPER STAIRS

Normal fold:Rigidly
folded with walls on each sideV type fold:Doesn’t really work for
gentle slopesU
type fold:The
paper here is barely folded at all. If suspended
it would be at the mercy of any errant breeze.
But if used as a tipping platform then it could work quite well.

BOOT SWING

Rear string is
held at the ready

The string is
severed though means unknown at this point.

The boot
swings forwards, kicking off the next part of the machine. If a swing like this is to be the final part
of the machine then we might give it a very long swing but boots are not
aerodynamic at the best of times and the bigger swing that we have the more
chance of the boot twisting in midkick.

The boot might
also be needed to weighted in order to provide some real power.

By happy chance you'll have just enough time to read the rest of this introduction before the orderlies put the straitjacket back on and your doctor reconsiders allowing you access to the outside world.

The explanation for this out of sequence posting is that the class is currently making Rube Goldberg Machines as I mentioned in passing in a previous post [2]

What follows is some gathered from a few places, Wikipedia, Grant and some stuff that was written up on the board in class. It's posted here because it's too big to post into the Facebook Group.

....

Actually forget all that

INTRODUCTION (REDUX)

Here are some notes for the Rube Goldberg Machine. Posted here due to it being way to big to fit into the Facebook Group. Naturally I have included my own notes for the intellectual which may be found in its usual place at the end of the posting.

Rube Goldberg Machine notations.

Room Measurements:

Window wall to
door wall 5.4m pillar to pillar

Solid wall 5m
pillar to pillar

Pillar to light
rail 1.8m

Light rail to
light rail 2m

Average Marble
weight 15gm – Variations of 0.5mm to 1mm

Materials:

Polystyrene

plastic milk
bottles

Cardboard

Paper (naturally)

Glass

Recycled objects

Fire

String

Magnets

Propulsion:

Mentos/Coke:Adding Mentos to Coke will result in a very powerful fountain about
a meter high. But this height is not uniform and it is best used
as a finale [3]

Candle/Steam:With much of the track being made of paper using this might require a wooden or plastic housing to be added to the track.

Pendulum:Can be used to knock the next step over, a counterweight or, if attached to a threaded screw system it might unscrew itself [4]

Counterweighted cranes:At it's heart this is a pivot and screw the making of which is, thankfully, relatively simple.

Plastic BagsCould be used as a catching device if the catapult idea goes ahead. Might also work as a track for the marble or even as a hanger [6] for the larger sections of the track

Water or similar liquid:Water would work as a weight that raised the marble up if it were slowly emptied from the container and vice versa.

Swings and roundabouts:Because everything's better with a swing. [7]

Catapult and catching system

NOTES:

"Wait a minute! where's the zany madcap humour? Is this blogger posting his Alphabet challenge posts out of order? I can't deal with this! Someone shut down the Internet!" You might also have time to think "Hey.Warumdenke ichauf Deutsch?" if the orderlies have lost the key to your cell yet again.

You don't need to go looking for it or anything. Just imagine that you remember me mentioning it in an offhand and casual manner.

Apparently Diet Coke works best which is good because Coca Cola hasn't ever found anyone prepared to drink the stuff

Achieving a kind of Nirvana I suppose. There are a shortage of pendulum jokes on the Internet but the good news is there there is an even greater shortage of pendulum rule 34's

Probably not the use he envisioned when he ran around shouting Eureka! (Bonus points if you spotted the intentional mistake)

You know, for hanging things.

Don't believe me? Try dumping someone while on a swing. It can't be done